Positron annihilation at the Si/Si02 interface
نویسندگان
چکیده
Variable-energy positron annihilation depth-profiling has been applied to the study of the Si/SiOz interface in Al-gate metal-oxide-semiconductor (MOS) structures. For both nand ptype silicon under conditions of negative gate bias, the positron annihilation S-factor characteristic of the interface (Sint) is substantially modified. Temperature and annealing behavior, combined with known MOS physics, suggest strongly that Sint’depends directly on holes at interface states or traps at the Si/SiO? interface.
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